9 Dec
2005
9 Dec
'05
1:38 p.m.
Subject: Re: Legacy apps in Windows/OS X was Re: Old MS-DOS & Win Software
From: woodelf <bfranchuk at jetnet.ab.ca>
Date: Fri, 09 Dec 2005 11:25:09 -0700
To: General Discussion: On-Topic and Off-Topic Posts <cctalk at
classiccmp.org>
Chuck Guzis wrote:
The early NEC 8080 (round lid prior to 77ish) set the flags wrong
I believe it was the sign flag though I'd have to check. After IMSAI
and others dumped them for the big they redesigned to exactly match
the Intel 8080A, NEC part was 8080AF.
Allison
Hmmm, thought I just said that. One of the more
highly-touted performance
improvements in the V20/V30 was the implemenation of dual internal data
busses. In practice, I don't know if it made a huge difference in speed,
but NEC claimed up to a 30% improvement for som operations..
That was a long time ago ... the XT clone wars. Back then a M$ mouse $100.
No need to gouge the public with windows /85 :)
I thought it interesting that the 8080 emulation
of the V20/V30 emulated
the Intel 8080A and not tne NEC 8080A instruction set.
So what instructions did the NEC 8080A have different?
>Cheers,
>Chuck 
9 Dec
9 Dec
1:52 p.m.
On 12/9/2005 at 1:38 PM Allison wrote:
The early NEC 8080 (round lid prior to 77ish) set the
flags wrong
I believe it was the sign flag though I'd have to check. After IMSAI
and others dumped them for the big they redesigned to exactly match
the Intel 8080A, NEC part was 8080AF.
I thought it was interesting that although IMSAI wouldn't use the NEC 8080A
part on their CPU cards, they freely used it in their floppy controller.
Probably to use up old stock, who knows?
Cheers,
Chuck
(still got one of them old round-lid NECs)
6:19 p.m.
On Fri, 09 Dec 2005 10:52:21 -0800
"Chuck Guzis" <cclist at sydex.com> wrote:
On 12/9/2005 at 1:38 PM Allison wrote:
Sure. If you're stuck with incompatible old stock, stick it an
embedded application where it will run ONLY your own well-tested
code.
The early NEC 8080 (round lid prior to 77ish) set
the flags
wrong I believe it was the sign flag though I'd have to check.
After IMSAI
and others dumped them for the big they redesigned to exactly
match the Intel 8080A, NEC part was 8080AF.
I thought it was interesting that although IMSAI wouldn't use
the NEC 8080A part on their CPU cards, they freely used it in
their floppy controller. Probably to use up old stock, who
knows?
6872
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